U.S. Pat. No. 6,596,296 provides for “a composition of at least one biodegradable polymer fiber wherein the fiber is composed of a first phase and a second phase, the first and second phases being immiscible, and wherein the second phase comprises one or more therapeutic agents.” The immiscible phases allow for therapeutic agents incorporated into the composition to be partially protected from an adverse organic environment so as to maintain their biological function. However, the interface between the phases can be detrimental to the therapeutic agent and alter its function. Therefore, this invention proposes an improvement over and an expansion of this concept to allow for the protection of therapeutic agents in potentially damaging organic solvent environments.